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 * Copyright (c) 2014, 2017, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
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package com.oracle.svm.core.c.enums;

import org.graalvm.compiler.core.common.calc.UnsignedMath;

public class EnumArrayLookup extends EnumRuntimeData {

    private final long cOffset;
    private Enum<?>[] cToJava;

    public EnumArrayLookup(long[] javaToC, long cOffset, Enum<?>[] cToJava) {
        super(javaToC);
        this.cOffset = cOffset;
        this.cToJava = cToJava;
    }

    @Override
    protected Enum<?> convertCToJava(long cValue) {
        long arrayIdx = cValue - cOffset;
        if (UnsignedMath.aboveOrEqual(arrayIdx, cToJava.length)) {
            return null;
        }
        return cToJava[(int) arrayIdx];
    }
}
